There are a number of conventional processes for packaging integrated circuit (IC) dice. By way of example, many IC packages utilize a metallic lead frame. The die may be electrically connected to the lead frame by means of bonding wires or solder bumps that have been preformed on the active surface of the die. In general, the die and portions of the lead frame are encapsulated with a molding compound to protect the delicate electrical components on the active side of the die. In some applications, it is desirable to leave the back surface (opposite the active surface) of the die exposed; that is, not to encapsulate the back surface of the die with molding compound. By way of example, it may be desirable to leave the back surface of the die exposed in order to increase heat transfer out of the die. This is especially relevant for packages used in power applications. In such exposed die packages, the back surface of the die may be pre-coated with a thin metallic layer. In some applications, the metallic layer may be soldered directly to a printed circuit board (PCB) in order to further enhance the heat transfer out of the die.
While existing arrangements and methods for packaging integrated circuits work well, there are continuing efforts to develop improved packaging techniques that provide cost effective approaches for meeting the needs of a variety of different packaging applications.